In automotive applications, there is a push for energy efficiency. One way to increase efficiency of motor vehicles is to control the coolant flows to and from the internal combustion engine so that the engine operates at a peak operating temperature. It has been known to use switchable coolant pumps so that the coolant flow is switched off while the engine heats up from a cold start more quickly. Additionally, throttling of coolant flows is also known using a thermal management module; however, the known thermal management module valves only include provisions for providing the coolant at a single outlet temperature.
One known prior art valve used in connection with a thermal management system is disclosed in DE 10 2006 055 536. In this case, a rotary valve having two coaxial rotary valve bodies located within a housing are provided. Here the inlet is in an axial direction and, depending upon the location of the coaxial valve bodies, the coolant flow is directed to a first or second outlet that can be separately switched off and on in order to control the flow of coolant from the water pump to various heat exchangers used in connection with the engine and various other systems, such as an oil cooler. However, there is no possibility for providing different outlet temperatures from the device. Further, a separate actuator is required for each of the coaxial rotary valve bodies.
It would be desirable to provide a way for allowing coolant at different temperatures to be available to different motor vehicle systems and engine components. It would also be desirable to achieve this in a cost efficient manner within a minimum space requirement. It would also be desirable to control the position of the rotary valve bodies within such valves in defined and efficient manner.